Wildfire prevention

Hatchery Fact Sheet - Brainerd

Year Established: There have been 3 hatchery locations in the Brainerd area since 1922.

HISTORY

The Current Brainerd Hatchery was established in 1986.

Why was it established? To raise walleyes and white suckers. White suckers haven’t been raised since 1996.

What is the general technology used for the hatchery? It is a flow through system where water enters the top and cascades down to the bottom and into two holding tanks, going through each hatching jar on its way down.

Has the technology been modified since establishment? Major improvements were made in 2009. A telephone alarm system was added as well as a chlorine detector, recirculation abilities, and touch screen controls for temperature regulation. This was done to save money and help the environment by using less water and natural gas. It also eliminated the need for night watchmen. Other improvements have been new hatching jar valves and hoses and the addition of a big screen display for showing walleye production movies during tours. We also started treating all eggs with iodine in 2009. This is to hopefully eliminate any diseases such as VHS.

Fish Management

In general, fish management tools fall into one of four categories:

protecting and restoring habitats and water quality;

regulating the harvest;

stocking; and

public education.

Lake surveys and research provide the information used to select appropriate management tools.

WALLEYE MANAGEMENT

Minnesota has more walleye, walleye lakes, and walleye anglers than any other state. Each year, anglers harvest about 3.5 million walleye.

The best way to maintain walleye numbers is to protect critical habitats. Shore land zoning and related laws aid fish by controlling development and protecting spawning sites and aquatic plants that fish use for cover.

Stocking is another management tool used. Minnesota’s cool water hatcheries produce 2 - 5 million walleye fingerlings and millions of fry each year. Stocking can provide walleye fishing in lakes that lack spawning habitats but can otherwise support walleye. Stocking is also effective for lakes that have been “rehabilitated” or occasionally winterkill. Like any tool, stocking must be used appropriately. If misused, it will be ineffective or possibly harmful to existing fish populations. Stocked walleye may compete for food with other game fish, particularly largemouth or smallmouth bass.

Stocking a lot of small fish does not guarantee catching a lot of big fish. Fish managers estimate only 4 percent of the annual statewide walleye catch comes from stocked fish. The rest is the result of natural reproduction.

Loss of habitat, pollution, and increasing fishing pressure continue to be the biggest issues in walleye management. Everyone must work to improve water quality, control runoff and waterfront development, and maintain aquatic vegetation. Anglers, in addition, will need to comply with regulations and harvest only what they intend to use, for Minnesota to maintain a quality fishery.

WALLEYE PRODUCTION

Walleye begin spawning in April as water temperatures approach 45 degrees. Workers collect, then combine the eggs and milt from walleye spawning in the Pine River. Spawning usually ends in three to four weeks. In a typical season, 500-700 quarts of eggs are taken, with 125,000 eggs per quart. The fertilized eggs are transported to the hatchery and hatch in three weeks.

Annually, this operation produces 25 to 70 million walleye fry. The fry are stocked in area lakes and rearing ponds. The fry in rearing ponds are raised to fingerling stage by fall; then are stocked in area lakes.

Science Informing Management

What types of research help with management decisions for this hatchery? We have been tagging fish in the spawning run to see when and if they return. This helps us get an idea of when and how often they come up the river to spawn, how far they travel, and the amount of mortality. This could potentially dictate how many eggs we take to the hatchery. We currently put any extra walleye fry back into the water they originally came from. Studies are also being done to see if these excess numbers actually hurt the lake and we are trying to find the point where stocking should be cut off. This will help us from taking too many eggs.

What other factors are involved with management decisions involving this hatchery? We study our lake surveys and assessments to determine where walleye stocking may benefit a lake and where it would be a waste of time. This tells us how many walleyes we will need and in return how many fish to raise in the hatchery. Another factor that we can’t plan for is winterkill. We propose stocking lakes that we think may have or will winterkill. If they don’t winterkill we may have excess fry.

What types of research or other science activities occur along with the activities in this hatchery? We are constantly checking and adjusting water temperature, flow, dissolved oxygen, etc., in order to determine the best possible setting for the hatchery. If the walleye fry hatch too soon or too late, they may be weak and not make it in the wild.

How does the data collected and/or research conducted at this hatchery inform/affect fisheries managers and fisheries habitats? Every area wants their hatchery to be as effective as possible. Data and research is shared from office to office in order to improve hatching and hatchery methods around the state. Any new ideas that are come up with are tested and results are shared among managers.

TOURS & VISITS

Seasonal Tours Available, Reservations Required

We are unable to give tours to casual visitors due to staffing limitations.